Congenital ocular anomalies and ventricular septal defect in a dromedary camel (Camelus dromedarius).

A 5-wk-old female dromedary camel (Camelus dromedarius) was clinically diagnosed with bilateral corneal dermoids, incomplete congenital cataracts, a left persistent hyaloid artery (PHA), and a ventricular septal defect (VSD). The corneal dermoids were removed by lamellar keratectomy, and vision improved in the left eye. Thirteen months after dermoid surgery, the calf was presented for enlargement of the right eye. Glaucoma was confirmed in the right eye, and corneal fibrosis and cataract were noted in the left eye. Persistence of the VSD was confirmed by cardiac ultrasonography. The calf was euthanized, and necropsy findings confirmed VSD. Histopathologic examination revealed bilateral corneal thinning and fibrosis, cataracts with retrolental fibroplasia, and retinal dysplasia. Additional changes in the right globe were anterior segment dysgenesis, ruptured lens capsule, chronic phacoclastic uveitis, and retinal separation. The PHA was confirmed in the left eye.     

A modified laryngoplasty approach promoting ankylosis of the cricoarytenoid joint

Objective: To perform a modification to the standard laryngoplasty procedure in vivo that would result in ankylosis of the cricoarytenoid (CA) joint, and determine the stability provided to the abducted arytenoid in vitro. Study Design: Experimental study. Animals: Horses (n=8). Methods: Horses were assigned to either control laryngoplasty (n=3) or modified laryngoplasty (5) procedure. Endoscopic upper airway evaluations were used to measure right:left quotients 1 day and 3 months postoperatively to assess maintenance of abduction. Horses were euthanatized 3 months after surgery and larynges collected for measurement of translaryngeal impedance and histologic evaluation of CA joint ankylosis. Each specimen was exposed to increasing negative pressure with the sutures intact or cut while translaryngeal impedance was recorded. Data were analyzed using ANOVA with significance set at P<.05. Results: Loss of left arytenoid cartilage abduction at 3 months was greater in the control laryngoplasty group. Overall, impedance was significantly lower for the modified laryngoplasty group compared with the control laryngoplasty group and lower with the sutures intact than cut. Histologic evaluation of the joints confirmed fibrous bridging of the left CA joints of the modified laryngoplasty group. Conclusions: A modified laryngoplasty approach promotes ankylosis of the CA joint and decreases the loss of abduction of the arytenoid.     

Opto-electronic counters for postlarvae and juveniles of Machrobrachium rosenbergii (de Man); design and tests of Type A counter

Postlarvae or juveniles of Macrobrachium rosenbergii produced in Mauritius are sold at unit price to prawn farmers and are counted individually by hand. This process is time consuming, labour intensive, subject to error and may stress the juveniles; safe rapid electronic counting would be highly advantageous.The design of the hydraulic component of a successful counter prototype, Type A, is described. The counter has 10 parallel channels through which juveniles are carried in a water current. The detection of juveniles passing through these channels can be done photo-electrically. The counter accepts juveniles up to 15 mm in length (eye orbit to tip telson) and has the significant advantage that it can be constructed using only simple hand tools.Survival and growth rate tests, and microscopic examination for damage to appendages of juveniles were done on machine counted and hand counted juveniles. There was no reduction of growth or survival caused by passage through the counter by comparison with the hand counting method, and it is concluded that the counter is not detrimental to juvenile prawns.About 70% of all juveniles tested showed highly variable amounts of damage. The great majority of this damage appears to originate in the hatchery tanks, prior to the experimental treatments. Only in the case of antennules could the use of the counter be shown to increase damage significantly, i.e. from 25% to 38%, but this has no detectable effect on subsequent survival or growth.This appears to be the first counter made specifically for counting macroscopic crustacean juveniles, and via suitable scaling, adaptation to counting other species of crustaceans, fish larvae, etc., should be possible.     

Influence of ectomycorrhization and cesium/potassium ratio on uptake and localization of cesium in Norway spruce seedlings

Norway spruce (Picea abies (L.) Karst.) seedlings growing in a growth pouch system were used to investigate the effects of the ectomycorrhizal fungus Hebeloma crustuliniforme (Bull. ex St. Amans) Quél. and various Cs/K ratios on the uptake of (134)Cs, expressed as a percentage of the total amount of (134)Cs supplied. The amount of (134)Cs taken up by seedlings increased with increasing Cs/K ratio. At a Cs/K ratio of 0.1, uptake of (134)Cs ranged between 7.2 and 7.3% and was independent of ectomycorrhizal status, whereas at Cs/K ratios >/= 1 uptake of (134)Cs varied from 8.1 to 11.1% for ectomycorrhizal and from 10.4 to 14.4% for non-inoculated plants. Ectomycorrhizal seedlings contained a lower concentration of (134)Cs than non-inoculated seedlings. Among plant parts, the amount of (134)Cs was significantly lower in needles and lateral roots of ectomycorrhizal seedlings compared with non-inoculated seedlings. Among fungal and seedling tissues, highest X-ray net counts of (133)Cs were measured in fungal hyphae of ectomycorrhizal mantles. X-Ray net counts of (133)Cs in lateral roots of ectomycorrhizal and non-inoculated plants were similar, but 5 to 10 times higher than in main roots and needles, suggesting an accumulation of (133)Cs in lateral roots and slow translocation to other plant parts. In contrast, X-ray net counts of K indicated that K was readily mobilized from lateral roots to main roots and needles. Elemental mapping showed a relatively homogeneous distribution of (133)Cs within the root.     

Persistence and colonization of gaps in sown swards of grass and clover under different sward managements

The effects of extensive sward management and patch size on the persistence and colonization of gaps in sown swards was examined by creating gaps of five different sizes (2·3, 7, 10, 14 and 19 cm in diameter) in four different sward treatments: a fertilized sward grazed to 4 cm, i.e. relatively intensive management, and three extensively managed unfertilized swards, which were not grazed or grazed to 4 cm or 8 cm. The swards were originally sown with ryegrass (Lolium perenne L.) and white clover (Trifolium repens L.), but had developed differences in species composition as a result of the management treatments imposed 2 years before and during the experiment. Light quality measurements, i.e. red-far red (R/FR) ratio, were used to determine when the light environment in the gaps no longer differed from that in control, uncut patches and this was used as an estimate of gap persistence. Persistence of gaps depended on both sward management and gap size. Gaps disappeared most rapidly in the ungrazed sward and fertilized 4-cm sward, and most slowly in the unfertilized 8-cm sward. Small gaps persisted for up to 2 weeks in all but 8-cm swards, whereas larger gaps were estimated to persist for up to 20–25 weeks in unfertilized, grazed swards. There was no evidence that the number of grass or dicotyledonous species increased in the gaps compared with the control areas. There were significant positive linear relationships between the vegetation that developed in gaps and that in the control, uncut patches, reflecting the different species composition of the established sward of the grazed (grass-dominant) and ungrazed (Ranunculus repens-dominant) treatments. For total grass dry matter and tiller numbers, as well as L. perenne tiller numbers, there was a small, but significant, effect of both patch size and sward management on the slopes of the regressions between the controls and gaps. The results are discussed in relation to the potential for species composition of sown swards to change as a result of gap creation.